Influence of the oxygen content on the transport and magnetic properties in layered manganites La2−2xSr1+2xMn2O7+δ with x being around 0.5

The role of the oxygen content in influencing the structure and physical properties of double layered manganites La2−2xSr1+2xMn2O7+δ with x∼0.5, has been investigated by means of X-ray diffraction, resistivity and magnetization measurements. The variation in the oxygen content causes the same physical effect as the Sr concentration, leading to a change in carrier density. In particular, the magnetic behavior seems to be influenced more with a change of the oxygen content than by that of Sr concentration. We will display the oxygen content-dependence on the magnetic and transport properties and discuss the role of the oxygen content in the double layered manganites with x∼0.5.